Disciplinarydefinition
Biophysicsistheapplicationofphysicsconceptsandmethodstostudytherelationshipbetweenvariouslevelsofbiologicalstructureandfunction,thephysical,physicalandchemicalprocessesoflifeactivities,andtheactivitiesofmatterinlifeThebranchofbiologythatshowsthephysicalcharacteristicsoftheprocess.Biophysicsaimstoclarifythelawsofmovementofmatter,energyandinformationinacertainspaceandtime.
Disciplinarydevelopment
Inthe17thcentury,Coopermentionedtheluminousfirefly;Galvanistudiedtheelectrostaticpropertiesofmusclesin1786;In1796,YangusedlightwavetheoryandcolorvisionTheory,studiesthegeometricandopticalpropertiesoftheeyeandthefluiddynamicsoftheheart;Helmholtzappliesthelawofconservationofenergytobiologicalsystems,andbelievesthatthematerialworld,includinglife,canbeattributedtomotion.Hestudiedtheheatproductionandtheconductionspeedofnerveimpulsesduringmusclecontraction;Dubois-Raymondwasthefirsttocreateanammeterandusedittostudymusclenerves.In1848,hediscoveredrestingpotentialsandactionpotentials.
AfterRoentgendiscoveredX-raysin1896,theywereappliedtomedicalpracticealmostimmediately.In1899,Pearsonmentionedforthefirsttimeinthebook"TheGrammarofScience":Thebiophysicsofphenomena..."andlistedthebloodfluiddynamics,electricalphenomenaofnerveconduction,surfacetensionandmembranepotential,luminescenceandbiologicalfunctions,aswellasmechanicalstress,elasticity,viscosity,hardnessandbiologicalstructure.Relationshipandotherissues.
In1910,Hillappliedelectricaltechnologytoneurobiology,andshowedthatthecharacteristicofnervefibertransmittinginformationisaseriesofuniformelectricalpulses,whicharecausedbythepotentialdifferencebetweentheinsideandoutsideofthemembrane.Theapplicationofmicroscopesinthe19thcenturyledtothecreationofcelltheory,andthedevelopmentofelectronmicroscopesprovidedmoreinformationaboutbiologicalultrastructures.
Asearlyas1920,X-raydiffractiontechnologyhasbeenincludedinthestudyofproteinstructure.AsteburyusedX-raydiffractiontechnologytostudythestructureofhair,silkandwoolfibers,andfoundthattheproteinbackboneconformationformedbyaminoacidresiduechains;WatsonandCrickproposedthegeneticmaterialDNAdoubleinthe1950s.Spiralcomplementarystructuremodel.When"MedicalPhysics"in1944introducedbiophysicalcontent,itcoveredawiderangeofareas,includingthestructureandfunctionofhearing,colorvision,muscle,nerve,skin,etc.,andreportedtheuseofelectroncyclotronstostudybiologicalobjects.
PhysicsconceptshaveagreaterimpactonthedevelopmentofbiophysicsinSchrödinger’slecturein1943:"Whatislife"andWiener’sargumentonbiologicalcybernetics;theformerusesthermodynamicsandquantummechanicstoexplaintheessenceoflifeTheconceptof"negativeentropy"wasintroduced,tryingtoexplainthematerialstructureoforganisms,themaintenanceandcontinuationoflifeactivities,andthegeneticsandmutationsoforganismsfromsomenewways;Transformation,storageandhandling.
Theybelievethatsincelivingmatterisacomponentofthematerialworld,ithasitsspeciallawsofmotionandshouldalsofollowthecommongenerallawsofmaterialmotion.Thisconnectsthetwofieldsofbiologyandphysics.
Sincethe1920s,ithasbeendiscoveredthatbiomoleculeshaveferroelectric,piezoelectric,semiconductor,andliquidcrystalproperties,andtheelectromagneticpropertiesoflifesystemsatdifferentlevels,aswellasthewidespreadradiofrequencycommunicationmethodsinthebiologicalworld.andmanymore.However,thesignificanceandroleofmanyphysicalcharacteristicsinlifeactivitiesarefarfromclear.
In1980,itwasdiscoveredthattwoartificiallysynthesizedDNAfragmentswereleft-handeddoublehelix.Peoplegenerallyhopetoknowwhetherthereisleft-handedDNAinnature;Doesrightrotationmeanthatleft-handedDNAdoesnotexistinnature?Thesignificanceofthisspecificopticalrotationtolifeactivitiesisstillunanswered.
Accordingtothephysicalcharacteristicsoforganisms,variousphysicalparameterscanbemeasured.However,duetothecomplexityoflivingsubstances,theparametershavetobechangedunderdifferentenvironmentalconditions.Existingtestingmethodsareoftennotapplicable,andtechnologicalbreakthroughsarestillneededtofurtherclarifythemysteriesoflife.
Thestudyofelementaryparticles(electronsandprotons)thatareactiveinlivingorganismsisalsoamajorpartofthephysicalandphysicochemicalprocessofexploringlifeactivities.Livingorganismsareallwater-containing,andstudyingthebehaviorofelectronsinaqueoussolutionsisextremelyimportantforunderstandingthephysicalandchemicalprocessesoflifeactivities.Peoplehavediscoveredbiologicalprotonstates,delocalizationofprotons,andprotontunneling.Therefore,furtherresearchinquantumbiologyisneededtoexplorethebehavioroftheseelementaryparticlesinvivo.
Inphotosynthesis,theinitialabsorptionofphotonsbychlorophyllisonlycompletedinonequadrillionthofasecond.Thevisualprocessandtheinitialenergyabsorptionofhigh-energyionizingradiationarealsocompletedinaninstant.Theseenergyareinthelivingbody.Theinitialwhereaboutsandbehaviors,fromabsorptiontotheappearanceofphysicalandchemicalprocesses,whatphysicaleffectsaretakingplace,thisrequiresbothsensitiveandrapidtestingtechniques.
Proteinisdenaturedataround56℃,butwecanstillfindorganismsinhotspringsabove70℃;artificiallyculturedcellsarestoredatminus190℃,andthecellsremainthesameasnormalafterthawing.TheseorganismsWhatisthestructuralstateofthewater?Ifwecanclarifythestructureandpropertiesofwaterintheseextremestates,itwillhelpourunderstandingofthelawsoflife.
DisciplinaryConnotation
Intheprocessofhundredsofmillionsofyearsofevolution,organismsfinallychosemembraneasthemostbasicstructuralform.Almostalllifeactivitiesfrompermeability,identification,communication,toenergyconversionarecarriedoutonthemembrane.Notonlydoesthemembraneprovideaplace,italsoactivelyparticipatesintheactivities.
Sometimestheemergenceofatechnologywillgreatlychangetheresearchofbiophysicalproblems.Forexample,X-raydiffractiontechnologyhasledtotheemergenceofmolecularbiophysics.Therefore,althoughtechnologyitselfdoesnotnecessarilyrepresentbiophysics,itisverycrucialtothedevelopmentofbiophysics.
Biophysicsisthephysicsofstudyinglivingmatter.Althoughlifeisanadvancedformofmovementinnature,itisstillamanifestationofthecomprehensivemovementofthethreequantities(mass,energyandinformation)innature.It'sjustthatthiskindofmovementchangeinthephysiologicalbodyiscomplicatedandrapid,andwiththecomplexityofthestructureofbiologicalmaterials,theuseofenergybecomesmoreandmoresophisticated,andtheamountofinformationbecomeslargerandlarger,makingtheresearchdifficult.Butontheotherhand,studyingthephysicallawsoflivingmattercannotonlyfurtherclarifythenatureoflivingthings,butmoreimportantly,itcanbringpeople'sunderstandingofthelawsofmovementoftheentirematterinnaturetoanewheight.